# 1251 HW 6 #13

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I'm having trouble finding the charge Q on the capacitor. (Part B)
asked Oct 5, 2014

Suppose the switch has been closed for a length of time sufficiently long for the capacitor to become fully
charged. ( = 8.50 V, r1= 10 kΩ, and r2= 14 kΩ.)

(b) Find the charge Q on the capacitor.

After a long time, the capacitor should be charged to a voltage so that no current would flow through it and the 3.00KΩ. Therefore, the voltage across the capacitor would be equal to the voltage across the resistor R2, while treating the capacitor branch as open circuit -- no current would flow through when charged.

Find the voltage across R2 in steady state by finding and using the current going through the resistor. With the voltage found, the charge can also be found with $C\Delta V_2=Q$.

answered Oct 5, 2014 by (21,750 points)